Soy milk

I was attempting to follow a recipe to make my own today... it turned out
pretty disgusting. Frankly, the storebought stuff was a lot better, but
it's so much more expensive than just buying the flour? Does anybody have
a better recipe or an adaptation of the following? Is the cider vinegar
important (cause I didn't add any)?
1/2 cup soy flour
3 cups water
1 tbsp maple syrup
1 tsp vanilla
1/2 tsp cider vinegar
Thanks.
--Dave
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